U-Turn Over VASCAR Decision?

The police in Scotland announced on the 5th February that they were reversing the decision, announced just one day earlier, advising officers to stop using the VASCAR speed detection system.  Apparently Home Office scientists have confirmed that the devices are in fact reliable. 

The Association of Chief Police Officers in Scotland (ACPoS) have said,

They had now received advice from the Home Office Scientific Development Branch that there was no possibility of interference when guidelines were followed by officers.
Acpos said that the equipment had been tested and found to operate properly under the appropriate guidelines.  

Now forgive me for pointing this out, but what happens when they are operated under ‘inappropriate’ conditions?  Does this mean that there is still an issue with the devices?

Apparently the Home Office has advised the following,

Despite the all-clear being given, the Home Office said officers should not use radios or mobile phones while using the device.

Now to me, this suggests there may still be some kind of an issue with the devices when used at the same time as radios and mobile phones!  Why say don’t use your mobile phone or radio if there is absolutely no reason for concern about the validity of speeding convictions.

In section 5 of the Association of Chief Police Officers Traffic Committee Enforcement Technology National Guidance Manual (the how to do it book) it says,

It is impossible to obtain complete immunity from radio interference.

As well as,

It is not possible to lay down a strict criteria for safe operating distances from transmitters. The strength of the interference depends on several factors, such as transmitter frequency, type of aerial and modulation system.

Now, surely this must throw some small measure of doubt on speeding convictions obtained using these devices.  What about all the people convicted before this all came to light and the Home Office ‘guaranteed’ their accuracy? 

I don’t know, maybe the authorities are just trying to head off loads of claims for falsely obtained convictions!

Previous entries on the same subject
VASCAR May Suffer From Interference.
Faulty Speed Cameras Could Wipe Out Speeding Convictions

Sources
Police’s U-turn over VASCAR speed detectors
Acpos does U-turn over use of speed detectors by Scots police forces
Police speed detectors ‘reliable’
In use for 30 years, but are speed units accurate?